(navigation image)
Home American Libraries | Canadian Libraries | Universal Library | Community Texts | Project Gutenberg | Children's Library | Biodiversity Heritage Library | Additional Collections
Search: Advanced Search
Anonymous User (login or join us)
Upload
See other formats

Full text of "The manufacture and properties of iron and steel"

150
METALLURGY OF IKON AND STEEL.
it is necessary to know the amount theoretically required. According to von Jtiptner the heating and melting of the stock calls for 328,250 calories per ton; in the former experiment I had called it 290,000 calories. Taking an average of the two gives about 310,000 calories, which will be the figure used in the new work. Tables VIII-A, B and C show the detailed calculation, the methods being as follows:
The carbon of the fuel minus the carbon in the ash gives the total carbon in the gas. Total carbon in the gas divided by the carbon in one cubic meter gives the volume of gas produced. Carbon in one cubic meter is found from the principle that one cubic meter of either 0, C02, or CH4 contains 0.54 kg. of carbon; C2H4 contains twice that weight. The calorific value of the gas is found by multiplying the volume of each combustible ingredient by the calorific power of one cubic meter of the combustible gas, and adding the products. The products of the dry distillation of the coal are taken from results on a similar coal at the beginning of distillation, coked in Semet-Solvay coke ovens, as reported by Prof. H. 0. Hofman. The volume of CH4 and C2H4 in the gases may be assumed as coming all from this distillation; the volume of H gas distilled off is a little less than the CH4. The volume of CO and C02 in the total gases, minus that coming from the distillation, gives the CO and C02 formed by combustion in the producer. The total volume of free hydrogen produced, minus that coming from the distillation, gives the free hydrogen liberated in the producer by the decomposition of steam. The total weight of hydrogen in the gas in every form (CH4, C2H4, H and H20) minus the weight of hydrogen in the coal in any form (assumed as 4 per cent, in the dried coal and 0.5 per cent, present as hygroscopic water) gives the hydrogen which must have comd in with the blast. Assuming average humidity of the air, the weight of hydrogen present in it as- moisture is calculated; the difference between this and the total hydrogen of the blast is, the hydrogen coming in from the steam jet, whence the weight of steam blown in.
The heat created in the producer is from formation of CO and C02. Some of this is rendered latent by being absorbed in the decomposition of KLO in the blast. This heat reappears in the open hearth when the gases are burnt; it is part of their calorific power. The rest of the heat created in the producer is lost as sensible heat